Service manual

1.2 DRUM UNIT
1. Make sure that the drum unit is set in position and secured with
the screw when the main switch is turned on. If the drum unit is
loose, poor contact of the drum connectors may cause electrical
noise, resulting in unexpected malfunction (RAM data change is
the worst case).
2. Clean the green color filter on the drum unit top plate with a dry
cloth and discharge static electricity by touching it with your
finger. Do not clean the filter with water or any other cleaning
solution as the filter has an antistatic coating.
1.3 CHARGE CORONA
1. Clean the corona wires by sliding the corona unit in and out. (The
cleaner pads come into contact with the corona wires when the
corona unit is slid all the way out.) The wires can be also cleaned
with water. Do not use sandpaper or a solvent.
2. Clean the charge corona casing with water first to remove NOx.
Then clean it with alcohol if any toner still remains on the casing.
3. Clean the end blocks with a blower brush first to remove toner
and paper dust. Then clean it with alcohol if any toner still
remains on it.
4. Do not touch the corona wires with oily bare hands. Oil stains
may cause white bands on copies.
5. Make sure that the corona wires are correctly positioned between
the cleaner pads and that there is no foreign material (iron filings,
etc.) on the casing.
6. When installing new corona wires, do not bend or scratch the
wire surface to avoid any uneven charge. Also be sure that the
corona wires are correctly positioned in the rear end block and
that the damper rings are correctly positioned in the front end
block. (See charge corona wire replacement.)
7. Clean the charge grid plate with a blower brush (not with a cloth).
8. Do not touch the charge grid plate with oily bare hands. Also, do
not bend the charge grid plate or make any dent on it. Doing so
may cause uneven charge.
9. The corona wire height should only be adjusted when the front
end block is replaced.
Rev. 10/92
FT5733/5433 4-2 FSM